Impact ring unit for disc mill



Jan. 21, 1964 R. R. DILL ETAL IMPACT RING UNIT FOR DIsc MILL Filed Jan. 25, 1960 2 Sheets-Sheet 1 Jan. 21, 1964 R. R. DlLL ETAL 3,113,524

IMPACT RING UNIT FOR DISC MILL Filed Jan. 25, 1960 2 Sheets-Sheet 2 INVENTORS Play/919D A. D I l l "/71? V/IV G/A/fl VE/V United States Patent 3,118,624 lF/TPACT RlNG UNIT FOR DISC MILL Richard R. Dill, Elrnhurst, ill and Marvin E. Ginaven, Springfield, Ohio, assignors to The Bauer Bros. (10., Springfield, Ghio, a corporation of Ghio Filed .lan. 25, 1960, Ser. No. 4,425 8 Qiaims. (Cl. 241-251) This invention relates to a novel impact ring unit adapted for use in attrition type mills. It is particularly advantageous when applied to a disc refiner and will be described with reference thereto. However, it must be understood that the application of the invention is not intended to be limited thereby.

The pulp and starch industries are constantly searching for means and methods for improving the efi'lciency of refining procedures. The primary objectives, of course, are to produce pulp products of higher quality at a minimum cost.

The present invention provides means for simply and economically introducing an additional milling stage in a conventional mill whereby, in the alternative, its capacity can be substantiflly increased with maintenance of product quality or the quality of product it produces can be improved while its normal capacity is maintained.

As applied to a disc refiner, the impact ring unit in accordance with the invention is disposed in concentric spaced relation to the discharge opening from the refiner discs so as to utilize the kinetic energy of the materials discharged to additionally refine such materials and expedite their discharge.

The object of the invention is to simplify the construction as well as the means and mode of operation of impact mills, whereby such mills may not only be economically manufactured, but will be more eflicient and satisfactory in use, adaptable to a wide variety of applications, and be unlil-zely to get out of order.

A further primary object of the invention is to provide refiner apparatus in the nature of an impact ring unit which can be applied to any attrition mill so as to increase its efiiciency without increasing its cost of operation.

A further object of the invention is to provide a novel ring type impact unit particularly applicable to attrition type mills.

An additional object of the invention is to provide a novel impact unit wherein the impact elements are arranged to seat transversely of a ring structure.

A further object of the invention is to provide an improved impact ring unit having a deflector type base.

A further object of the invention is to provide an impact mill possessing the advantageous structural features, the inherent meritorious characteristics and the mode of operation herein mentioned.

With the above and other incidental objects in view as will more fully appear in the specification, the invention intended to be protected by Letters Patent consists of the features of construction, the parts and combinations thereof, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawing wherein is shown one but obviously not necessarily the only form of embodiment of the invention,

FIG. 1 of the drawing is an elevation view, partly in section, of a double disc refiner embodying the invention;

FIG. 2 is a view taken on line 2-2 of FIG. 1 with disc details eliminated for clarity of disclosure;

FIG. 3 is a view taken on line 3-3 of FIG. 4;

FIG. 4 is an enlarged fragmentary view of an impact ring unit as provided by the invention; and

FIG. 5 is a top perspective view of the portion shown in FIG. 4.

Like parts are indicated by similar characters of reference throughout the several views.

The drawings illustrate a preferred embodiment of the invention. A conventional disc refiner is shown in generally diagrammatic fashion. it is detailed only to the extent necessary to illustrate the invention principles and concepts.

As shown in FIG. 1 of the drawings, the refiner 1 includes a housing 2 centrally thereof enclosing a pair of opposed axially aligned refiner discs 3 and 4. The oper ating faces of the discs are immediately adjacent and slightly spaced to mutually define a peripheral discharge opening. Motors 5 and t, disposed to either end of the housing 2 conventionally connect to discs 3 and 4 at their centers by means of their respective drive shafts 7 and 8. A chute 9 leading to an opening centrally of the disc 3 provides means for introducing pulp between the discs. The housing 2 is otherwise sealed except for a discharge opening 10 in its bottom.

It may be seen from FIG. 2 of the drawings that the crosssection of the upper portion of the housing 2 is semicircular while its lower half is defined by side panels 11 which are first generally parallel and then converge in hopper-like fashion to define the discharge opening 1%.

An impact unit 12 in accordance with the invention mounts to the inner wall of housing 2 concentric with and in slightly spaced relation to the peripheral discharge opening defined between the operating faces of the discs 3 and 4 at their periphery. The unit 12 is formed in four quadrants. The upper quadrants are arcuate at their outer peripheral surfaces to mate with the upper portion of the housing 2 and be fastened thereto by bolts 13 at their respective extremities. The lower quadrants which mate to complete the ring type unit 12 have the outermost surfaces of their remote ends modified to seat to the generally parallel portions of panels 11 and be bolted thereto. The lower quadrants are otherwise in the form of 99 arcs and are connected at their abutting ends by a bridging plate 14 bolted thereto.

The base or outermost portion 15 of the ring unit 12 is generally triangular in cross-section, its sides 16 being inwardly convergent with respect to the housing 2. Instead of the sides converging to a point, they converge to an apex 17 which is rounded so as to smoothly diverge from its center which generally lies in a plane defined between the discs 3 and 4. A series of transverse channels 18 are provided in the inner peripheral portion of the base 15 of unit 12, generally equidistantly spaced thereabout. The channels 18 have a depth substantially equal to the depth of the apex portion of the base. Each channel respectively nests a bar or pin 19 on its side which is generally cylindrical but flattened at its seating surface to conform to the configuration of the channel. The bar elements 19 are welded or otherwise suitably fixed to the base 15 to uniformly project inwardly thereof approximately one half their cross-sectional depth. This provides an encircling ring about and spaced from the discharge opening from the discs 3 and 4 consisting of spaced, generally parallel, transversely disposed impact elements forming semi-cylindrical projections inwardly from the relatively divergent sides of the base 15.

In operation of the invention apparatus, material is led into the housing 2 through chute 9 to a central position between the refiner discs as they are rotated in opposite directions by their respective drive motors 5 and 6. The opposed faces of the discs 3' and 4 provide impact surfaces between which the material is defiberized as it is moved radially outward to discharge between the peripheral portions of the discs under the pressure of incoming material and under the in nce of centrifugal force. The refined material discharges quite violently and must strike the inner peripheral portion of ring unit 12 due to its orientation.

Thus, the material refined between the impact surfaces of discs 3 and 4 is flung against a third impact surface provided by the ring unit 12. this manner the kinetic energy of the di charged material is utilized for a further refining procedure rather than merely being dissipated as occurs in the conventional disc refiner. A two-fold influence is exerted by the ring unit 12 as the refined pulp material impacts on the projected portions of the bars 19 which are transversely disposed relative the discs. First, an additional defiberizing of the pulp takes place on impact to further free undesirable ingredients contained therein. Secondly, a circular deflection of the pulp material occurs and it also strikes the inner peripheral contour of the ring base 15 intermediate the bars 1). The outward divergence of the sides of the base 15 causes the material striking it to deflect away from the discs 3 and 4- to opposite walls of the housing 2 and fall free in a gravity discharge through the opening 1% The fact there are no fiat impact surfaces on the unit 12 insures that materials dischar ed from between the discs will not be thrown back so as to clog the discharge opening therebetween as sometimes occurs in conventional refiners. lso, the contour and orientation of bars 19 and the innermost surface of the ring base 15 prevents material discharged from adhering and building up between the bars 19. Thus, the invention provides an additional impact in a conventional disc refiner insuring a continuous uniform flow of refined material. Its use inherently enables a definite increase in quantity and/ or quality of the pulp produced in a particular refiner without increase in power requirements.

The invention ring unit will increase the capacity of any conventional refiner since it creates better discharge conditions. Quality is increased thereby since more useful work is accomplished. Economy results since the advantages obtain Without increase in power consumption.

While the invention has been particularly described in application to the refining of pul or starchy materials, other materials to be refined are not excluded thereby.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advanta es.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not imited to the specific features shown, but that the means and construction herein disclosed comprise but one of several modes of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described our invention, We claim:

1. impact apparatus including a base element forming a closed loop having an interior impact surface which is generally convex in cross-section and impact elements seated in transversely nested relation to and projected from the innermost surface portion thereof, the relatively projected surface portions of said impact elements also being convex but in a sense generally at right angles to the convexity of said impact surface.

2. Refining apparatus including a pair of opposed relatively rotatable plates having their working faces in adjacent relation to define a discharge opening therebetween at their periphery, means to relatively rotate said plates, means to deliver materials to be refined between said plates to be impacted on and defiberized thereby and centrifugally discharged through said opening, and means about said plates and adjacent said opening oriented in the plane and the path of materials discharged therethrough having an adjacent surface which is convex in a sense generally at right angles to the plane of discharge through said opening and impact elements nested transversely of and projected from said adjacent surface in the direction of said opening and presenting convexly rounded surface portions thereto for circularly deflecting materials discharged in the general plane of their discharge to be impacted on and laterally deflected by said adjacent convex surfaces.

3. in combination with a disc mill including milling means and a housing thereabout, a ring-like element projected from the inner wall of the housing in the general plane and path of discharge from said milling means and transversely oriented impact elements projected from the inner surface of said ring-like element in spaced relation thereabout and in the direction of said milling means, the relatively projected surface portions of said impact elements being arcuately formed to induce circular deflection of materials discharged from said milling means in opposite senses and in the general plane of said ring-like element.

4. In combination with a disc mill including milling means and a housing thereabout, a ring-like element pro jected from the inner Wall of the housing in the general plane and path of discharge from said milling means and transversely oriented impact elements projected from the inner surface of said ring-like element in spaced relation thereabout and in advance thereof with respect to said discharge, the relatively projected surfaces of said transversely oriented elements being cylindrical providing impact surfaces which induce circular deflection of the discharge to an additional impact surface in the form of the projected ring-like element.

5. in combination with a disc mill including milling means and a housing thereabout, a ring-like impact element projected from the inner wall of the housing in the general plane and path of discharge from said milling means, said ring-like element having a projected surface which is bluntly convex in cross section in a sense transverse to the path of discharge from said milling means, said projected surface being elongated in said transverse sense to extend across said discharge path and acting to both defiberize material impacted thereon and deflect it laterally from the general plane and path of the discharge from said milling means.

6. in combination with a disc mill including milling means and a housing thereabout, a ring-like element projected from the inner wall of the housing in the general plane and path of discharge from said milling means, the projected surf-ace of said ring-like element being generally rounded cross section, and transversely oriented impact bars nested in the innermost surface of said ring-like ele ment and relatively projected therefrom in spaced relation thereabout, the projected surface portions of said impact bars being convexly rounded in the plane of said ring-like element.

7. In combination with refiner apparatus including a housing and refiner means contained therein, means in said housing an impact surface in the general lane and path of discharge of material from said refiner means, said impact surface being generally convex relative the discharge and means defining additional impact surfaces in advance of and oriented transversely of the ,rst mentioned impact surface formed so as to be operative to deflect circularly the discharge impacted thereon to the first mentioned impact surface, in the general plane thereof.

8. Refiner impact apparatus, including ring-like means, transversely oriented impact elements projected from the: innermost surface of said ring-like means in spaced relation thereabout, the relatively projected surface of said transversely oriented elem nts being generally cylindrical. providing impact surfaces capable of circularly deflecting materials impacted thereon in opposite sense to an additional impact surface provided by the innermost surface portions of said ring-like means adjacent thereto.

References Cited in the file of this patent UNITED STATES PATENTS 263,571 Parrnenter Aug. 29, 1882 304,682 Gorton Sept. 2, 1884 636,666 Holmes Nov. 7, 1899 780,581 Rich Jan. 24, 1905 855,981 Rice June 4, 1907 1,591,938 Harrison July 6, 1926 1,614,409 Surtees Jan. 11, 1927 6 Van Pelt Feb. 20, 1934 Lykken Sept. 8, 1942 Dodds et al. Sept. 8, 1953 Meyer Feb. 16, 1954 Lecher May 31, 1955 FOREIGN PATENTS Great Britain Sept. 15, 1899 Austria Oct. 26, 1959 OTHER REFERENCES Mineral Industry, vol. 47, page 682, 1938. 

1. IMPACT APPARATUS INCLUDING A BASE ELEMENT FORMING A CLOSED LOOP HAVING AN INTERIOR IMPACT SURFACE WHICH IS GENERALLY CONVEX IN CROSS-SECTION AND IMPACT ELEMENTS SEATED IN TRANSVERSELY NESTED RELATION TO AND PROJECTED FROM THE INNERMOST SURFACE PORTION THEREOF, THE RELATIVELY PROJECTED SURFACE PORTIONS OF SAID IMPACT ELEMENTS ALSO BEING CONVEX BUT IN A SENSE GENERALLY AT RIGHT ANGLES TO THE CONVEXITY OF SAID IMPACT SURFACE. 